The signification and method of HBeAg gray zone setting and its cut-off verification in chemiluminescent assay
10.3760/cma.j.issn.1009-9158.2012.11.016
- VernacularTitle:HBeAg化学发光法临界值验证和灰区设定的方法探讨及意义
- Author:
Cheng AN
;
Shi CHENG
;
Jie LI
;
Guijian LIU
- Publication Type:Journal Article
- Keywords:
Chemiluminescent measurements;
Hepatitis B e antigens;
Indicators and reagents;
Reference values
- From:
Chinese Journal of Laboratory Medicine
2012;(11):1045-1047
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the signification and method of Cut-off verification and gray zone setting in chemiluminescent assay.Methods NCCLS EP-12 A2 document defines that C50 is the analyte concentration of cut off value for immunology qualitative test and C5-C95 interval is the range of analyte concentration that yields 5% positive results to 95% positive results for immunology qualitativc test.The C50 and C5-C95 interval of HBeAg in ARCHITECT i2000 were worked out according to the cut off value provided by HBeAg reagent calibrated in ARCHITECT i2000,which were verified to approve the character declaimed by manufactory or not.Gray zone was set and the procedure of cut off verification and gray zone set in chemiluminescent were built; A set of quality control was detected 20 times with two different lot HBeAg reagent kits,S/CO was caculated and compared with t test.Results C50 and C5-C95 interval of reagent (lot 06087L100,96378HN00) were 0.171 PEI U/ml,0.125 PEI U/ml; >0.154 PEI U/ml to 0.188 PEI U/ml,0.119 PEI U/ml to <0.150 PEI U/ml,respectively.S/CO of negative quality control and positive quality control were (0.550 ±0.038),(2.422 ±0.084) and(0.334 ±0.063),(3.587 ±0.321),respectively.They all approved the character (the sensitivity at cut off was less than 0.5 PEI U/ml)declaimed by manufactory,and the results of S/CO between two lot kits were obvious difference (t =9.944,15.499,P <0.01).Conclusion C50 and C5-95 interval can be used to verify cut off value and set gray zone in chemiluminescent assay;They may vary in different lot reagents and they must be verified to approve the character declaimed by manufactory.